采用HPB235级钢筋做受力筋时，两端需设弯钩，弯钩形式不包括( )。
A．45°B．90°C．135°D．180°
参考答案：A
怀疑急性肾小球肾炎应及时作肾活检的指征为
A．高血压
B．大量蛋白尿
C．明显浮肿
D．肾小球滤过率进行性下降或病情于2个月尚未见全面好转者
E．肉眼血尿
Many man-made satellites _____ up into space by many countries.[ ]
A. sent
B. have sent
C. has been sent
D. have been sent
